Tool post



April 3, 1928. v v 1,664,851

G. M. CLASS TOOL POST ed Aug. 1926 2 Sheets-Sheer 1 5/ O J 55 5 J2 i K1; 12 I $2 5 10- 3 Q7 22 19 29 22' 26 JTzI- QJZZOW: Geor gzM Class April3, 1928.

TOOL POST Filed Aug. 18- 1925 a l 2 Sheets-Sheet 2 Jill/6775 14 J3 Gzojgajfi (YZLS 5 2, w Jm 1,664,851 e. M. CLASS Patented Apr. 3, 1928o VUNITED STATES.

PATENT OFFICE.

GEORGE M. CLASS, OE. MADISON, WISCONSIN, ASSIGNOR TO GISHOL'I. MAOHINECOM- PANY, OF'MADISON, WISCONSIN, A CORPORATION OF WISCONSIN.

'roor.

Application August 18, 1926-. Serial No. 129,885.

This invention relates to tool posts 'for lathes and other machine toolsemploying tool posts, andhas reference more particularly to' tool postsof the turret type capable of holding a plurality of tools and of beingindexed to bring the latter successively into operative relation to thework. A The main object of the present invention is to provide a verysimple, inexpensive and eflicient tool post, in which, by swinging ahandle lever through an angle slightly greater post will be indexed andclamped. 'Another object is to provide an improved and simplified,mechanism for unlocking the tool holder when the latter is to beindexed.

In the accompanying drawings I have illustrated the invention asembodied in a square turret tool post designed to be in dexed through anangle of ninety degrees but it will be understood, of course, that theinvention is equally applicable to tool posts designed to be indexedthrough greater or less angles. V I 7 Referring to the drawings- 3 Fig.1 is a top plan view;

Fig. 2 is a vertical section line 2+2 of Fig. 1;

Fig. 3 is a horizontal section taken on the talien on the a line a-a ofFig. 2;

Fig. 4 is an elevation; and J Figs. 5 and 6 aredetailperspective viewsof a rotatable sleeve through which the retracting movements of thelocking bolt are efiected.

Referrin to the drawings, 10 designates the base 0 the tool post that ishelddown on the cross-slide 11 '(Fig. 4) by bolts 12 and nuts 13, whichlatter are adjustable in the usual T-slots 14 of the cross-slide. The

ofthe base 10 is circular,

upper portion 10' the tool holder body and mounted thereon is 15equipped with the usual lateral flange 15' 1 carrying screws 16 by whichthe tools are clamped on the wedges 17. Extendingcoaxiall through thebase 10 and body 15 is a stu 18 that is formed with a threadedlower end19, a threaded upper end 20, and an enlarged central portion 21. On thethreaded lower end 19 of the stud is a nut 22 adapted to move'intoclamping and-release engagement with the bottom of the than the indexingangle, the tool base, as hereinafter described, and pinned to the upperthreaded end 20 of the stud is an operating arm 23. The tool holder body15 is furthercentered and revolubly guided on the base by a circularflange 24 on its lower end embracing the circular upper portion 10' ofthe base.

Referring to Fig. 2, mounted in the base 10 is a bushing 25 in which isslidablymounted a locking bolt 26 chambered in its lower portion tohouse a thrust sprin 27 by which it is normally pressed upward y intoone of a series of sockets 26' formed at spaced intervals in the bottomof the tool holder 15. The spring 27 is footed on a pin 28 that ismounted in a lug 22 formed as a lateral extension of the clam ing nut22. The nut 22 is also formedwit a vertical slot 29 that accommodates alateral projection or foot 30 formed on the locking bolt 26.

Encircling the stud 18 below its central enlarged portion 21 is arotatable sleeve 31, shown in isometric detail in Figs. 5 and 6 Saidsleeve has a circumferential bearin in the bore of the base 10 and iscon ed against any substantial end pla downwardly by the hut 22 andupwardly y co-operating annular shoulders 32- and 33 on the sleeve 31and its bearing in the base 10, respectively. -The lower end-of thesleeve 31 is formed to provide a plurality of spaced with the foot ofthe lockingbolt to hold the latter retracted during the indexingmovement of the tool holder.

The sleeve 31 is turned in one direction only; of the sleeve .isformedwith a plurality of ratchet teeth 38, these teeth co-operatin'g and forthis purpose the upper end with a pawl 39 that is mounted to slidevertically in a hole in the enlarged portion 21 of the stud 18. The'pawl39 is pressed downwardly into oo-operating en agement with theratchet bya spring 40. ss'uming that the lower end of the'pawl 39 is in'conpermitthe locking bolt to re-engage with the next socket in the tool holder;

Similar pawl and ratchet .mechanism is preferably employed to transmitthe turning movement of the stud 18 to the tool holder; this last-namedpawl and ratchet mechanism being timed to operatein immediate successionto the operation of the bolt retracting mechanism, so that the toolholder may be unlocked, then indexed to a new position, andautomatically relocked by a single continuous movement in one direc tionof the operating arm or lever 23. 'The mechanism for turning the toolholder is best shown in Fig. 3, wherein it will be seen that the bore ofthe tool holder which forms in part a bearing for. the enlarged portion21 of the stud is formed with a plurality of spaced ratchet teeth 41,which, for greater durability are preferably formed in hardened steelpins 42 non-rotatably fitted into .seats in the tool holder body.Co-operating with the ratchet teeth 41 is a pawl 43 that is slidablehorizontally in a transverse hole in the stud section 21 and urgedoutwardly by a spring 44. The operation has been for the most part'setforth in the fore oing de scription of the structure, but may e brieflyoutlined as follows.

The bolt retracting cams 36 being, in the instance shown, about thirtydegrees long the first thirty degrees of swinging movement of the arm 23in a counterclockwise direction efiects the retraction of the bolt. Atthat point the pawl 43 comes into engagement with one of the ratchetteeth 41; and the continued swing of the arm 23 in the same directionthrough another ninety de grees efiects the indexing of the tool holderto a new position, at which point the foot of the locking bolt dropsinto another notch 34 of the cam sleeve and the bolt simultaneouslyengages with the next socket of the tool holder andthus locking thelatter in its newly indexed position. When the operating arm is reversedthrough the same are as its forward movement, the nut 22 is drawn utight-against the base 10 clamping the whole post rigidly together, andthe pawls 39 and 43 snap back into position again as the operating armis reversed, ready to effect the next unlocking and indexingmovement ofthe post. If more than ninety degrees is to be indexed at one time, bymoving the opformed on itslower-end with a lateral erating armsufliciently to withdraw the locking bolt, and then moving the toolholder the rest of the way by hand, and then reversing the arm the toolpost may be clamped in any position. A 1 a I claim- 1. In a toolpost,the combination of a base, an upwardly springressed locking bolt insaid base formed wit a lateral rojection, a tool holder rotatable onsaid ase having sockets in its under side to interlock with the upperend of said bolt, a rotatable stud extending centrally through said baseand tool holder, said stud formed with an enlarged intermediate portion,an operating arm fast on the upper end of said stud, a

rotatable sleeve encircling said stud beneath said arm in the samedirection after said bolt has been retracted.

2. In a tool post, the combination of a base, an upwardly spr 1ngpressedlocking bolt in said base formed with a lateral rojection, a tool holderrotatable on said ase having sockets in its under side to interlock withthe upper end of said bolt and internal ratchet teeth, a rotatable studextending centrally through said base and tool holder,

said stud formed with an enlarged interme-' portion embraced by theupper porsaid base and the lower portion of diate tion 0 said toolholder, an operating arm fast on the upper end of said stud, a rotatablesleeve encircling said stud beneath said enlarged portion, said sleeveformed on its lower end with. cams cooperating with said projection toretract said bolt, pawl and ratchet means carried by said enlargedportion andthe upper end of said sleeve for turning the latter,

and a horizontally slidable ring-pressed pawl mounted in said enlargeportioncooperating with the internal ratchet teeth of said tool holderto index the latter by a continued movement of said arm in the samedirection after said bolt has been retracted.

3. In a tool ,post, the combination of a base, an" upwardly'spring-pressed locking bolt eccentrically' mounted in said base androjection, a tool holder-rotatable onsaid base having sockets in itsunder side to interlock with the upper end of said bolt, a rotatablestud extending centrally through said baseand tool holder, an operatingarm fast on the upper end of said'stud, a nut on the lower end of saidstud adapted for clampiiao ing engagement with said base, cooperatingsleeve for turning the latter, and pawl and means carried by saidlocking bolt and nut ratchet means carried b said stud and tool forlocking the latter against turning, a roholder operative to in ex thelatter by 9.

tatable sleeve encircling said stud formed on continued movement of saidam in the same 5 its lower end with cams coogzrating with directionafter said bolt has been retracted.

said projectionto retract'said lt, pawl and ratchet means carried bysaid stud and GEORGE M. CLASS.

